Next victim 1998, Evinrude 150, Head O rings,J150EXECD

[pastorbud]

Got the head off one side of my 98 Evinrude 150 (J150EXECD). Had good compression on all but #1 and #3. Looks like a problem with the O rings in the head, but those water passages don’t look so good, either. They’re easy to clear, though. Not clogged solid.

 

[pastorbud]

BTW, when I tried to check compression on 1 and 3, pressure would build to about 110, then the engine would “kick over”, causing the starter bendix to disengage.

A friend of mine said a head gasket (in this case, O ring) problem could cause that.

 

[pastorbud]

Ima “if it works don’t fix it” kinda guy, but those clogged water passages make me wanna open the other head and look at that side too.

 

[pastorbud]

Ima “if it works don’t fix it” kinda guy, but those clogged water passages make me wanna open the other head and look at that side too.

 

[Faztbullet]

Find a different friend as it don't take much pressure to kick out the bendix on a gear reduction starter.... Clean the heads,install new o- rings, silicon the head and put it together....If you don't have a FACTORY manual get one....

 

[pastorbud]

Roger. (He’s still a pretty good friend, maybe just not that good an outboard mechanic! 🛠⛏)

 

[pastorbud]

Here’s the starboard cylinder head. Obviously cylinders one and five have not been playing nice. But how did RTV get INSIDE the water passages?

 

[pastorbud]

Zoomed in to show RTV in water passages.

 

[Faztbullet]

But how did RTV get INSIDE the water passages? ​

Cause the factory put it there.....your RTV the whole outer edge of head when reinstalling, those holes do nothing as water cools head internally. Thus the need for factory manual...

 

[pastorbud]

Cause the factory put it there.....your RTV the whole outer edge of head when reinstalling, those holes do nothing as water cools head internally. Thus the need for factory manual...

Thanks for the feedback. I had already downloaded the manual. Let me make my question more clear: Since the manual says to place a bead AROUND each passage, isn’t it a little surprising to find the sealant IN some of the passages?

 

[Faztbullet]

No it is not unusual to find the sealer in those holes....I usually just run a bead around the outside perimeter...lea prevention. Make sure you use the shiny wet glossy look RTV and not the flat black . I use Peratex Blk silicon adhesive from Auto Zone

 

[pastorbud]

Got it, thanks!

 

[jerryjerry05]

Maybe the sillycone was applied by a robot?
The starter kicking out? rebuild it.

 

[pastorbud]

Cleaning up the head. Making progress. Figure eights on sandpaper on a hard flat surface.

Number 1 cylinder is the problem child.

 

[Chris1956]

Bud, Hopefully that flat hard surface is a piece of plate glass, as it needs to be absolutely flat, to keep/make the head true. Also use a new piece of crocus cloth to finish up.

 

[pastorbud]

Bud, Hopefully that flat hard surface is a piece of plate glass, as it needs to be absolutely flat, to keep/make the head true. Also use a new piece of crocus cloth to finish up.

Uhhh...well, it’s a big piece of ceramic floor tile! (Stop laughing!)

But I checked it on multiple angles with a straight edge. Just did a different head last summer using the same piece, and it worked okay. As the folks on TV say... “Your results may vary.”

I did see a big old thick glass mirror at the Habitat for Humanity Re-Store the other day. Almost grabbed it.

I’ve also heard polished granite counter top pieces work.

 

[Chris1956]

Not sure ceramic or granite substitutes for glass. Ceramic tiles are molded, and are usually slightly different from each other. Granite is sawed from blocks. Not sure how accurate the cuts are. Certainly they are within 1/64" or so, but not sure that is enough.

Plate glass is made by pouring molten glass onto liquid tin. It naturally lies flat and finds a uniform thickness and smoothness.

 

[pastorbud]

Prolly gunna buy that mirror! That’s plate glass, isn’t it?

 

[pastorbud]

There we go

 

[Chris1956]

That mirror should be plate glass.

Just so you know, before the table rolling method, window glass used to be blown. A glass blower would blow a bottle, and then cut off the neck and bottom, leaving a cylinder. He would then cut the cylinder down the middle and heat it up until it flattened out. That is why old windows had many small lites, rather than large panels.

You can often see imperfections in old window glass, from the blowing process.